Don---I am certainly in "learn as I go" mode on this windshield thing. I have a Brookville catalogue here, and it appears as if only the 28 and 29 model A's had a fixed angle one peice windshield post. The posts which they offer for the 30/31 series seems to have a 2-peice post with a hinged joint in it similar to the 1932 models. I can only assume that if people wanted to run their convertible top on the 30/31 models, that they would have to adjust the posts to set verticaly, similar to the 28/29, but if they weren't using their top they could loosen off the big wing nut at this joint and lean the posts back. The reason that I have had a dialogue with the Topster guys from B.C. is to see if I can come up with a method of attaching their top to the posts on my roadster pickup, which of course has cut off sedan windshield posts. I have solved this issue by welding a plate into the top of my posts to close them off, and putting a 3/8" threaded hole into the plate. I will make adapter stubs the same diameter as the top of a model A windshield post, with a 3/8" threaded shank on them. When they are screwed into place, this will enable me to use a conventional convertible top header.